Process control systems, like those used in chemical, petroleum or other processes, typically include one or more process controllers and input/output (I/O) devices communicatively coupled to at least one host or operator workstation and to one or more field devices via analog, digital or combined analog/digital buses. The field devices, which may be, for example, valves, valve positioners, switches and transmitters (e.g., temperature, pressure and flow rate sensors), perform functions within the process such as opening or closing valves and measuring process parameters. The process controllers receive signals indicative of process measurements made by the field devices and/or other information pertaining to the field devices, use this information to implement a control routine, and then generate control signals that are sent over the buses or other communication lines to the field devices to control the operation of the process. In this manner, the process controllers may execute and coordinate control strategies using the field devices via the buses and/or other communication links communicatively coupling the field devices.
Process control systems are often configured to perform processes in accordance with recipes to produce products. Product designers or engineers prepare recipes during a design time and store the recipes to be subsequently used a plurality of times by a process control system. A recipe typically includes a combination of unit procedures, operations, and phases, all of which include instructions to control process equipment (e.g., tanks, vats, mixers, boilers, evaporators, pumps, valves, etc.) to transfer, mix, etc. ingredients in a process control system to generate a product.
To display recipes, some known systems use a procedural function chart (PFC) including blocks for each process step or phase of the recipe. During execution of the recipe, the PFC shows which process step or phase is currently being executed so that an operator or other user can see which part of the recipe is being executed. This type of status information of those known systems is very high level, general information that merely informs a user of a step or phase in a recipe that is currently being executed without any other information specific to that step or phase such as, for example, pressure measurements, temperature measurements, progress (e.g., percent complete) of that particular phase, etc. In some known systems, such phase characteristics can be viewed via a terminal by navigating away from the PFC to display phase characteristics corresponding to particular process steps or equipment selected by a user. In other known systems, a user must visually inspect the physical equipment used to implement the recipe to determine phase characteristics of a particular step or phase by, for example, reading gauges. The disconnection between the PFC display of a recipe and the phase characteristics of process steps or phases in the above-described known systems requires that a user leave or navigate away from a PFC display of a recipe to observe phase characteristics corresponding to the status of the recipe execution, thereby burdening users with having to remember, organize, and coordinate all of this information when navigating between different screen views.